Prognostic value of exercise stress echocardiography in patients with known coronary artery disease

Funding Acknowledgements

Type of funding sources: None.

Background

Exercise stress echocardiography (EE) is useful for diagnosis and risk stratification in patients (pts) with suspected coronary artery disease (CAD). Pts with known CAD carry a high risk of events. Our aim was to assess the utility of EE in predicting outcomes in this population.

Methods

Single center retrospective study of consecutive pts with known CAD who performed an EE between 2018 and 2019. The primary endpoint was a composite of admission for acute coronary syndrome (ACS), coronary revascularization and cardiovascular death during the follow-up.

Results

A total of 76 pts were included (mean age 59±9 years; 87% male). Fifty-nine (78%) pts had history of ACS, 51 (67%) of percutaneous coronary intervention (PCI) and 14 (18%) of coronary artery bypass graft. The majority of pts had 2 or more vessel disease (42 pts; 55%).

The main reason for performing EE was new onset of chest pain (38 pts; 50%) followed by functional assessment of coronary stenoses after incomplete revascularization (29 pts; 38%). The majority of pts had a preserved left ventricular ejection fraction (67; 88%). The exam was performed under beta-blocker effect in 35 (46%) pts.

The results of EE were positive for myocardial ischemia in 7 (9%) pts, negative in 37 (49%) pts and inconclusive in 32 (42%) pts. Mean exercise time was 8±3 minutes and mean METs achieved was 9.4±2.6. ST-segment depression fulfilling electrocardiographic criteria for ischemia occurred in 17 (22%) pts. Eleven (14%) pts complained of chest pain during the exam.

During a median follow up of 22 months (IQR 15-26), the primary endpoint occurred in 9 pts (admission for ACS in 5 pts; revascularization for chronic coronary syndrome in 4 pts). No cardiovascular death occurred. The positive predictive value of EE for the primary endpoint was 57.1% and the negative predictive value (NPV) 97.3%.

In a survival analysis, the predictors of the primary endpoint were lower exercise time, lower METs achieved, untreated significant coronary lesions and a positive EE (figure).

After adjustment in a multivariate analysis, a positive EE was an independent predictor of the primary endpoint (HR 4.6, 95%CI: 1.1-16.7, p=.044).

Conclusion

In pts with known CAD, EE had a high NPV and a positive result was an independent predictor of future cardiovascular events.

A left systolic dysfunction study in a group of breast cancer patients and its clinical impact

Funding Acknowledgements

Type of funding sources: None.

Background

 Cancer therapy-related cardiac dysfunction (CTRCD) is one of the major complications being reported in patients with breast cancer (BC) under chemotherapy, in particular with anthracyclines (A) or trastuzumab (T). CTRCD is defined as a reduction of left ventricular ejection fraction (LVEF) >10% to a value <50% or as a relative reduction of global longitudinal strain (GLS) >15%.

Purpose

We aim to evaluate the frequency of CTRCD and its clinical impact on BC patients.

Methods

 Retrospective study of patients with BC treated with A and/or T between Jan 2017 and Dec 2018 who underwent a  transthoracic echocardiography (TTE) before, during, and after chemotherapy. We analysed their baseline characteristics and outcomes based on the type of treatment received, and focusing specially on parameters of ventricular function.

Results

 We included 128 females with median age of 54 ± 11 years-old, treated with A (78; 60.9%), T (14; 10.9%) or A followed by T (36; 28.1%).

At the end of A therapy, there was a significant decrease in LVEF (64,2 ± 5,4% vs 62.6 ± 5,3%, p < 0.05) and in GLS (-20,7 ± 1.9% vs -18.8 ± 2.2%, p < 0.001) compared to baseline. No change in tricuspid annular systolic velocity (S") (p = 0,842) was observed. At 2 years of follow-up, this group of patients had no significant difference in LVEF (64,58 ± 5,58 vs 62,63 ± 6,48, p = 0,053) but maintained a significant lower GLS (-20,84 ± 2,13 vs -18,51± 2,52, p < 0,001) compared to baseline. A significant decrease in S’ (14,36 ± 2,55 vs 13,25 ± 2,26, p < 0,05) was observed.

During T therapy, there was a significant decrease in LVEF (65,04 ± 5,41 vs 59,30 ± 6,21, p < 0,001), in GLS (-21,21 ± 2,75 vs -17,89 ± 2,77, p < 0,001) and in S’ (14,39 ± 3,05 vs 12,19 ± 1,62, p < 0,001) compared to baseline. At the end of T therapy (with or without A), this group of patients maintained a significant decrease in LVEF (65,11 ± 5,65 vs 61,29 ± 6,39, P < 0,001) and in GLS (-21.41%±2,86 vs -19.54%±3,50, p < 0,01). S’ returned to normal values (p = 0,10). At 2 years of follow-up, this group of patients maintained a significant decrease in LVEF (65,00 ± 5,99 vs 61,18 ± 6,30, p < 0,05) but GLS (p = 0,235) returned to normal values. No change in S’ was observed (p =0,379).

During a mean follow-up of 38 months, 35 (27%) patients developed CTRCD with a higher prevalence in patients who took A followed by T (18; 14%), 9 (7%) presented with clinical heart failure, 1 (1%) needed hospitalization, 5 (4%) needed to temporarily suspend treatment and 3 (2%) needed to definitely stop treatment.

Conclusions

 Treatment with A was associated with a decrease in LV systolic function at the end of therapy. A decrease in right ventricular (RV) systolic function was observed at 2 years of follow-up. Treatment with T was associated with a decrease in RV and LV systolic function during therapy. CTRCD occurred in 27%, mainly on patients with both A and T therapy, a frequency within literature data. CTRCD had clinical impact leading to HF and suspension of chemotherapy.

Cancer therapeutics-related cardiac dysfunction: what is the role of cardioprotective medication?

Funding Acknowledgements

Type of funding sources: None.

Introduction

Cancer therapy-related cardiac dysfunction (CTRCD) is one of the major complications being reported in patients with breast cancer (BC) under chemotherapy, in particular with anthracyclines (A) or trastuzumab (T). Guidelines recommend regular left ventricular ejection fraction (LVEF) assessments and CTRCD management with cardioprotective medication (CPM). However, while secondary prevention has already entered clinical practice, primary prevention is still in the research domain.

Purpose

Our aim was to evaluate the role of CPM and the risk of CTRCD in BC patients.

Methods

Retrospective study of BC patients treated with A and/or T between Jan 2017 and Dec 2018 who underwent a transthoracic echocardiography (TTE) before, during, and after chemotherapy. Patients with baseline LVEF <50% were excluded. CTRCD is defined as reduction of EF >10% to a value <50% or as relative reduction of global longitudinal strain (GLS) >15%. As CPM we considered angiotensin-converting enzyme inhibitors (ACEI), angiotensin receptor blocker (ARB) and beta-blockers (BB).

Results

We included 128 patients, all female with median age of 54 ± 11 years-old, treated with A (78; 60.9%), T (14; 10.9%) or A followed by T (36; 28.1%).

At baseline, mean LVEF was 64,7 ± 5,7% and mean GLS was -20,8 ± 2,3.

During a mean follow-up of 38 months, 35 (27%) patients developed CTRCD with a higher prevalence in patients who took A followed by T (18; 14%), 9 (7%) presented with clinical heart failure, 1 (1%) needed hospitalization, 5 (4%) needed to temporarily suspend treatment and 3 (2%) needed to definitely stop treatment. ACEI/ARB therapy was initiated in 12 (34%) and BB therapy was initiated in 10 (29%). Twenty-one (60%) of CTRCD patients recovered. CPM initiation after CTRCD was not associated with a significant higher rate of cardiac function recovery (p = 0,682).

When comparing patients already medicated with CPM before cancer treatment (39; 30,5%) to those naïve of CPM, the first group presented a lower incidence of CTRCD (7% vs 20%) but it was not statistically significant (p = 0,473).

In patients treated with T or A + T, the group of patients treated with CPM before cancer treatment did not present a significantly lower incidence of CTRCD (p = 0,449) compared to patients CPM naïve. Nonetheless, there was a significant higher LVEF in the TTE during T therapy, after chemotherapy and at 2 years of follow-up (P <0,05) in patients treated with CPM before cancer treatment compared to patients CPM naïve.

In patients treated with A (without T) there was no statistically significant difference between the two groups.

Conclusion

 In our study, pre-treatment with CPM was associated with a significant higher LVEF in patients treated with T but no significant association was found with respect to the occurrence of CTRCD. CPM initiation after CTRCD was not associated with a statistically significant cardiac function recovery.

Impact of an inconclusive exercise stress echocardiogram on cardiovascular outcomes

Funding Acknowledgements

Type of funding sources: None.

Background

Exercise stress echocardiography (ESE) is used for the assessment of suspected or known coronary artery disease (CAD); however, a certain percentage of ESE studies are inconclusive. We aim to evaluate the prognostic impact of an inconclusive ESE on cardiovascular outcomes.

Methods

Single-center retrospective study of consecutive patients (pts) who performed an ESE between 2018 and 2019 for diagnosis or stratification of CAD. All pts performed a symptom-limited Bruce protocol. ESE was considered inconclusive when 85% of age-predicted maximum HR was not reached. Primary endpoint was a composite of admission for acute coronary syndrome (ACS), coronary revascularization and cardiovascular death during the follow-up.

Results

A total of 141 pts were included (76% male; mean age 60 ± 9 years). ESE was inconclusive in 51 (36%) pts, positive in 11 (8%) and negative in 79 (56%).

The mean exercise time of pts with inconclusive ESE was 7 ± 2 minutes and 76% had normal functional capacity. Fatigue (25 pts; 49%) and lower extremities pain (11 pts; 22%) were the main reasons for ESE stopping. Five pts (10%) complained of chest pain during exam.

Pts with an inconclusive ESE were more diabetic (inconclusive 43%, positive 9%, negative 13%; p=.001), had more chronic obstructive pulmonary disease (COPD) (14%, 0%, 2.5%; p=.026), performed more frequently the exam under beta blocker (BB) therapy (59%, 27%, 18%; p=.041) and had less ST-segment depression fulfilling electrocardiographic criteria for ischemia (10%, 64%, 27%, p<.001). Their functional capacity was worse than negative ESE pts (p<.001).

During a median follow up of 22 months (IQR 15-27), 13 (9.2%) pts had the primary endpoint, including 5 pts (3.5%) with ACS.

Pts with an inconclusive ESE had a lower incidence of the primary outcome than pts with a positive ESE and a higher incidence of events than pts with negative results (figure).

In multivariate analysis, after adjusting for functional capacity and electrocardiographic criteria for ischemia, an inconclusive ESE was an independent predictor of the primary endpoint (HR 9.7, IC95% 1.1-87,6 p= .042)

Conclusions

The frequency of inconclusive ESE is not negligible (36%). These pts had more diabetes and COPD and performed the exam under BB therapy more frequently, highlighting the importance of proper patient selection. An inconclusive ESE was associated to a higher risk of cardiovascular events compared to negative ESE. Abstract Figure.

Prevalence and clinical impact of latent obstruction in hypertrophic cardiomyopathy

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is characterized by varying degrees of left ventricular outflow tract obstruction (LVOTobs). We aim to define the prevalence, clinical profile and impact of LVOTobs under physiological exercise in HCM patients (pts).

METHODS

Single center retrospective study of consecutive HCM pts without LVOTobs at rest (resting gradient <30mmHg), referred for exercise stress echocardiogram (ESE) between 2015 and 2019. Significative latent obstruction was defined as a LVOT gradient ≥50 mmHg during exercise or at early recuperation.

RESULTS

A total of 56 pts were included (64% men, mean age 57 ± 11 years, 61% septal HCM). The majority of pts (47; 84%) were in NYHA I functional class, 20 (36%) had history of syncope or pre-syncope (S/pS) and 7 (13%) had an implantable cardioverter defibrillator (ICD). Twelve (21%) pts had systolic anterior motion (SAM) of the mitral valve at rest.

Thirty-five (63%) pts performed ESE under beta-blocker (BB) therapy. Mean exercise time was 8 ± 3 min. During ESE, 2 (4%) pts developed a LVOT gradient between 30 to 50 mmHg and 17 pts (30%) developed a significative LVOTobs gradient (mean 85 ± 18 mmHg).

Pts with significative latent LVOTobs had more previous complaints of S/pS (59% vs 26%, p=.017), a tendency for a higher NYHA functional class (p=.082) and were more frequently on BB therapy (82% vs 18%, p=.043). Mean septum thickness was similar between groups (17 ± 0.7 vs 16 ± 0.6 mm, p=.536). The presence of SAM at rest was more frequent in the significative latent LVOTobs pts (p<.001). No differences were noted in exercise tolerance (p=.526).

During a median follow-up of 43 (IQR 15-53) months, 7 (41%) pts with significative latent LVOTobs had a pre-syncope, 3 (18%) were diagnosed with atrial fibrillation and 2 (12%) had a cardiovascular admission . There was up-titration/initiation of BB therapy in 5 (29%) pts, referral for septal myectomy in 3 (18%) and ICD implantation for primary prevention in 3 (18%) pts. No proper ICD shocks, sustained ventricular arrythmias or deaths occurred.

Comparing significative latent to non LVOTobs pts, the first ones had more ICD implantation (log rank p =.04) and performed a surgical myectomy more frequently (log rank p= .018) during the follow-up.

CONCLUSION

In our study, significative latent LVOTobs was observed in 30% of pts. Its presence can have clinical implications in HCM pts approach and should be suspected in more symptomatic pts and when SAM is present at rest.

Characterization of temporal trends of systolic and diastolic indexes over time in breast cancer patients treated with trastuzumab

Funding Acknowledgements

Type of funding sources: None.

Background

Trastuzumab therapy increases survival in patients (pts) with HER2 positive breast cancer, however, it is associated with a risk of cardiotoxicity (CT). Our aim was to: 1) assess the temporal evolution of systolic and diastolic left and right ventricular indexes during and after T therapy and 2) study the incidence of CT in this group.

Methods

Retrospective study of breast cancer pts treated with T in a single center, during 2017 and 2018, who underwent a comprehensive echocardiographic examination before, quarterly, and after conclusion of T therapy. Pts with a baseline left ventricular ejection fraction (EF) <50% were excluded. CT was defined as a reduction of EF >10% to a value <50% or as a relative reduction of global longitudinal strain (GLS) of more than 15%.

Results

We included 50 women with mean age of 56 ± 10 years and mean body mass index (BMI) of 27 ± 5 kg/m2. Thirty-six (72%) patients underwent anthracycline chemotherapy prior to T and 44 (88%) had performed radiotherapy.

During treatment with T there was an increase of indexed left ventricle end-diastolic volume (38.6 ± 7.8 to 46.5 ± 10.3 ml/m2, p<.001) and a reduction of LVEF (65.1 ± 5.4 to 59.3 ± 6.2%, p < 0.001), GLS (-21.2 ± 2.7 to -17.9 ± 2.8%, p<.001) and right ventricle S’ (14.4 ± 13.1 to 12.2 ± 1.6 cm/s, p<.001) compared to baseline. There was no change in diastolic function parameters.

CT occurred in 23 (46%) pts, the majority based on GLS criteria (18; 78%). Heart failure symptoms were reported in 4 (8%) of these pts (1 in the GLS group and 3 in the EF group) and 3 (6%) pts had to permanently suspend therapy with T due to CT.

Patients with CT had a lower BMI (25 ± 4 vs 29 ± 4 kg/m2), but were otherwise similar to pts without CT. No association was found between pre-treatment with anthracyclines or radiotherapy with the risk of CT.

An echocardiographic revaluation at 2 years from treatment with T revealed a tendency for LVEF improvement (58.7 ± 7.1 to 61.2 ± 6.3%, p=.059) and a significative recovery of GLS (-17.4 ± 3.5 to -19.1 ± 3.3%, p=.026). No significative variations were found on right ventricular systolic function indexes or on diastolic parameters.

During a follow-up of 43 (IQR 32–47) months, 7 (14%) pts had tumor relapse and 1 (2%) died. CT was not associated with the composite endpoint of tumor relapse or death (p = 0.585).

Conclusion

T therapy is associated with a significative reduction on left and right ventricle systolic indexes during treatment. Although left ventricle systolic function tends to normalize over time, this does not happen with the right ventricle. CT induced by T had clinical impact leading to overt heart failure in 8% of pts and treatment discontinuation in 6% of pts.  A lower BMI was associated with CT, which may be taken into account when defining the treatment strategy.

Electrophysiologic study for risk stratification in Brugada Syndrome: does it still matters?

Background

The value of eletrophisiologic study (EPS) with programmed ventricular stimulation for risk stratification in patients with Brugada Syndrome (BS) remains controversial.

Purpose

The aim of this study is to determine the clinical and electrocardiographic predictors of positive EPS and to evaluate whether the induction of malignant ventricular dysrhythmias in the EPS is a predictor of events

Methods

A retrospective study was carried out of patients with spontaneous type 1 Brugada pattern followed up in Arrhythmology consultation at our Hospital. From this population, patients who underwent EPS for stratification of dysrhythmic risk were selected. Clinical and electrocardiographic variables were analyzed. Hospital records and monitoring data from cardiac devices were consulted. Statistical analysis was performed using SPSS 20.0.

Results

Fourty nine patients were included, with a mean age at the beginning of follow-up of 45±14 years, 40 (82%) of whom were male. In 16 individuals (33%) the EPS was positive with induction of malignant ventricular dysrhythmias. All patients with positive EPS implanted an implantable cardioverter-defibrillator and of the 32 patients with negative EPS, 10 implanted an implantable event recorder. The group of patients with positive EPS had a higher proportion of male patients (88% vs 78%). The median follow-up time was 31 months.

The family history of sudden death, family history of BS, or identification of a genetic variant classified as pathogenic or probably pathogenic did not present any relationship with EPS positivity. Of the analyzed electrocardiographic markers, PR interval (178±29 vs 171±27) and QRS duration (119±24 vs 113±15) tended to be longer in patients with positive EPS. Additionally, it was found that 74% of patients with a QRS of less than 120 ms had a negative EPS.

In the analysis of the value of EPS in the stratification of dysrhythmic risk, it was found that of all the patients who suffered events (4), 75% had positive EPS. Of the patients with negative EPS, only 3% (1) presented events in the follow-up. However, there was no significant association between these variables.

Conclusion

In this population, the analysed clinical elements did not correlate with the EPS result. Although there was no statistical significance, there was a tendency for patients with narrower QRS to be more likely to have negative EPS. Accordingly with published data, it was found that the EPS result was not a predictor of events during the follow-up period, which highlights the difficulty of risk stratification in patients with BS.

Funding Acknowledgement

Type of funding sources: None.

Impact of atrial fibrillation and biventricular pacing percentage on long-term outcome in patients with heart failure treated with cardiac resynchronization therapy

Introduction

A history of preoperative atrial fibrillation (AF) has been found to be associated with unfavorable outcomes, higher risks of non-response to cardiac resynchronization therapy (CRT) and loss of biventricular pacing (BivP). We aimed to assess the impact of AF and BivP on long-term outcomes in heart failure patients treated with CRT.

Methods

We retrospectively enrolled 227 patients undergoing CRT implantation between 2013 and 2020 according to the current guidelines. 118 patients were included in our analysis, from whom all data were available. Clinical, electrocardiographic and echocardiographic parameters were evaluated at baseline and 6 months after CRT. Response to CRT was defined as an increase in left ventricular ejection fraction (LVEF) >10%. We considered an effective delivery of BivP >98%. The primary endpoint was the composite endpoint of hospitalization due to HF or death for any cause.

Results

118 patients were included (mean age 69±11 years, 66.1% males, 39.8% ischemic etiology; baseline LVEF was 27,6±6%). Patients were divided into AF (n=42; 35,6%) and sinus rhythm (SR (n=76); 18 patients had permanent AF. AF patients had higher index left atrial volume and left ventricular mass (p<0.001). Mean follow-up time was 43±18 months. BivP percentage was significantly superior in SR than in AF patients (98.1±2.1% vs 94.7±4.5%, p<0.001), with 75% of SR patients having BivP>98% vs 30,3% of AF patients (p<0.001). There were no differences in preoperative parameters between them. The response rate to CRT was higher in SR patients when compared to AF patients (63,2% vs 40,5%, p=0.021). Indeed, the variation of LVEF was higher in SR patients (12±10% vs 7±9%, p=0.012).

During follow-up, there were significant differences between AF and SR patients in the primary endpoint (73,8% vs 42,6%, p<0.001), and mortality for any cause (26,2% vs 9,2% p=0.014; p<0.001). In a multivariate logistic regression analysis pre-procedural AF and BivP (%) were the only independent predictors of primary endpoint (HR 8.949, 95% CI 2.429 – 32.972, p=0.001; HR 0.719, 95% CI 0.526 – 0.982, p=0.038, respectively). Kaplan-Meier curves showed that event survival free was higher in SR patients when compared to AF (69±4 vs 24±3 months, p<0.001)

Conclusion

Pre - procedural AF and BivP are independent predictors of the occurrence of a primary endpoint of hospitalization due to HF or death for any cause in HF patients submitted to CRT.

Funding Acknowledgement

Type of funding sources: None.

Right ventricular dysfunction is a predictor of non-response to cardiac resynchronization therapy

Introduction

Cardiac resynchronization therapy (CRT) has been of great benefit to many heart failure (HF) patients with reduced ejection fraction (EF) and intraventricular conduction delay. However, approximately 30% of patients fail to respond to CRT. We investigated baseline characteristics that might influence response to CRT.

Methods

We retrospectively enrolled 227 patients undergoing CRT implantation between 2013 and 2020 according to the guidelines. 118 patients were included in our analysis, from whom all data were available. Clinical, electrocardiographic and echocardiographic parameters were evaluated at baseline and 6 months after CRT implantation. Response to CRT was defined as an increase in left ventricular ejection fraction (LVEF) >10%. Right ventricular systolic dysfunction (RVSD) was defined as S' velocity <9.5 cm/s or tricuspid anular plane systolic excursion (TAPSE) <17 mm. Chronic kidney disease (CKD) was defined as GFR <60 ml/min/1.73m2.

Results

118 patients were included (mean age 69±11 years, 66.1% males, 39.8% ischemic etiology; 35,6% atrial fibrillation, baseline LVEF 27,6±6%). After 6 months of CRT, 65 patients (55.1%) were considered responders. Responders were more frequently female than non responders (43,1% vs 22,6, p=0.02). Atrial fibrillation and CKD were more prevalent in non responders (47,2% vs 26,2%, p=0.018; 62,3% vs 21,5%, p<0.001, respectively). RVSD was present in 60,4% of non responders vs 16,9% of responders (p<0.001). In responder group, the mean S' velocity was 10,9±2,1 cm/s vs 9,1±2,1 cm/s in non responder group, p<0.001. The mean TAPSE was also higher in responder group (20,3±7,2 mm vs 16,5±4,4 mm, p=0.031). On multivariate analysis only RVSD (OR 7,754; 95% CI 2,968 – 20,282 p<0.001] and CKD (OR 5,434; 95% CI 2,109 – 14,002; p<0.001) were independently associated with non-response to CRT.

Conclusion

From a range of preoperative characteristics, multivariate analysis only identified RVSD and CKD as independent predictors of CRT response, with S' <9,5 cm/s and TAPSE <17 mm associated with non-response to CRT. This study highlights the importance of routine RV assessment in order to improve patient selection and optimize CRT response in heat failure patients.

Funding Acknowledgement

Type of funding sources: None.

QRS narrowing predicts left ventricular reverse remodelling after resynchronization therapy in patients with end-stage heart failure

Introduction

Cardiac resynchronization therapy (CRT) is an established treatment for heart failure (HF) patients, however one-third of the patients fail to benefit from CRT. The relationship between the QRS duration, severity of mechanical dyssynchrony and efficacy of CRT is not completely understood. We determined if QRS duration shortening after CRT implantation was predictive of left ventricular reverse remodelling.

Methods

We retrospectively enrolled 227 patients undergoing CRT implantation between 2013 and 2020 according to the guidelines. 88 patients were included in our analysis, from whom all data were available, and these represent our sample. Clinical, electrocardiographic and echocardiographic parameters were evaluated at baseline and after 6 months of CRT implantation. Response to CRT was defined as a reduction in left ventricular end-diastolic volume (LVEDV) >15%. Linear regression models were used.

Results

88 patients were included (mean age 69±10 years, 62.5% males, 36.4% ischemic etiology). Baseline left ventricular ejection fraction (LVEF) was 27,5±5,8% and LVEDV was 181±69 ml. After 6 months of CRT, 52 patients (59.1%) were considered responders. Baseline LVEDV was superior in responders when compared with non responders (199±85 ml vs 168±53 ml, p=0.038). No significant differences were noted in male gender (p=0.823), ischemic cardiomyopathy (p=0.065), LVEF (p=0.853), atrial fibrillation (p=0.390), left bundle branch block (p=0.950) or biventricular pacing (p=0.154) between them.

QRS duration at baseline was similar between responders and non-responders (165±17 ms vs 163±17 ms, p=0.620). After 6 months of CRT, the reduction of QRS duration in responders was significantly higher than non-responders (p<0.001).

QRS duration was reduced from 165±17 ms to 136±15 ms in responders vs 163±17 ms to 160±17 ms in non-responders, (p<0.001). The change in QRS duration positively correlated with the change in LVEDV (0. 654; p<0.001). Multi-linear regression analysis suggested that QRS duration shortening had a significant effect on LVEDV (y = 14,375 + 1.354 X, R2 0.337, p<0.001)

Conclusion

QRS duration shortening after CRT implantation was predictive of LV reverse remodelling in end-stage heart failure patients. Further prospective studies should be conducted to assess the prognostic value of QRS narrowing in response to CRT.

Funding Acknowledgement

Type of funding sources: None.